Antimicrobial composition useful for preserving wood

ABSTRACT

Antimicrobial compositions useful for preserving wood, and comprising a variety of antimicrobial compounds.

This invention relates to combinations of biocides useful for preservingwood, the combinations having greater activity than would be observedfor the individual antimicrobial compounds.

Use of combinations of at least two antimicrobial compounds can broadenpotential markets, reduce use concentrations and costs, and reducewaste. In some cases, commercial antimicrobial compounds cannot provideeffective control of microorganisms, even at high use concentrations,due to weak activity against certain types of microorganisms, e.g.,those resistant to some antimicrobial compounds. Combinations ofdifferent antimicrobial compounds are sometimes used to provide overallcontrol of microorganisms in a particular end use environment. Forexample, U.S. Pat. No. 5,591,760 discloses a synergistic combination of4,5-dichloro-2-n-octyl-4-isothiazolin-3-one and a number of otherbiocides, including 3-iodo-2-propynyl-butylcarbamate, but this referencedoes not suggest any of the combinations claimed herein. Moreover, thereis a need for additional combinations of antimicrobial compounds havingenhanced activity against various strains of microorganisms to provideeffective control of the microorganisms that is both quick and longlasting. The problem addressed by this invention is to provide suchadditional combinations of antimicrobial compounds.

STATEMENT OF THE INVENTION

The present invention is directed to a synergistic antimicrobialcomposition comprising: (a) 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one;and (b) copper tebuconazole.

The present invention is further directed to a synergistic antimicrobialcomposition comprising: (a) 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one;and (b) 2-methyl-4-isothiazolin-3-one.

The present invention is further directed to a synergistic antimicrobialcomposition comprising: (a) a copper alkyldimethylammonium salt; and (b)copper 8-hydroxyquinoline.

The present invention is further directed to a synergistic antimicrobialcomposition comprising: (a) a copper alkyldimethylammonium salt; and (b)2-n-octyl-4-isothiazolin-3-one.

The present invention is further directed to a synergistic antimicrobialcomposition comprising: (a) copper 8-hydroxyquinoline; and (b)2-n-octyl-4-isothiazolin-3-one.

The present invention is further directed to a synergistic antimicrobialcomposition comprising: (a) copper 8-hydroxyquinoline; and (b)3-iodo-2-propynyl-butylcarbamate.

The present invention is further directed to a synergistic antimicrobialcomposition comprising: (a) tebuconazole; and (b) a microbicide selectedfrom the group consisting of4,5-dichloro-2-n-octyl-4-isothiazolin-3-one; copper 8-hydroxyquinoline;2-n-octyl-4-isothiazolin-3-one; and a mixture of5-chloro-2-methyl-4-isothiazolin-3-one and2-methyl-4-isothiazolin-3-one.

The present invention is further directed to a synergistic antimicrobialcomposition comprising: (a) propiconazole; and (b) a microbicideselected from the group consisting of4,5-dichloro-2-n-octyl-4-isothiazolin-3-one; copper 8-hydroxyquinoline;2-n-octyl-4-isothiazolin-3-one; a mixture of5-chloro-2-4-isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one; and3-iodo-2-propynyl-butylcarbamate.

The present invention is further directed to a synergistic antimicrobialcomposition comprising: (a) 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one;and (b) copper 8-hydroxyquinoline.

The present invention is further directed to a synergistic antimicrobialcomposition comprising: (a) 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one;and (b) thifluzamide.

DETAILED DESCRIPTION OF THE INVENTION

“MI” is 2-methyl-4-isothiazolin-3-one, also referred to by the name2-methyl-3-isothiazolone. “CMI” is5-chloro-2-methyl-4-isothiazolin-3-one. “DCOIT” is4,5-dichloro-2-n-octyl-4-isothiazolin-3-one. “OIT” is2-n-ocyl-4-isothiazolin-3-one. “IPBC” is3-iodo-2-propynyl-butylcarbamate. Copper tebuconazole is a biocideformulation containing a monoethanolamine complex of copper oxide andtebuconazole.

A “copper alkyldimethylammonium salt” is a biocide formulationcontaining a monoethanolamine complex of copper oxide and analkyldimethylammonium salt. In one embodiment, the alkyldimethylammoniumsalt is alkylbenzyldimethylammonium salt. In another embodiment, thealkyldimethylammonium salt is dialkyldimethylammonium salt. In anotherembodiment, the alkyldimethylammonium salt is an aryloxyethoxyethyldimethyl benzylammonium salt, wherein aryl preferably isdiisobutylphenyl or diisobutylcresyl. Preferably the salt is a chloride,carbonate or bicarbonate. Preferably, the weight ratio of copper oxideto alkyldimethylammonium salt is from 30:70 to 80:20. In one embodiment,the ratio of copper oxide to alkyldimethylammonium salt is from 55:45 to80:20, more preferably from 62:38 to 71:29. In another embodiment, theratio is from 35:65 to 65:35, more preferably from 45:55 to 55:45.Preferably the alkyl groups are in the range from C₈-C₁₈, with themajority being C₈-C₁₄. In one embodiment, the alkyl groups are 67% C₁₂,25% C₁₄, 7% C₁₆ and 1% C₁₈. In another embodiment, the alkyl groups arefrom C₈-C₁₂.

As used herein, the following terms have the designated definitions,unless the context clearly indicates otherwise. The term “antimicrobialcompound” refers to a compound capable of inhibiting the growth of orcontrolling the growth of microorganisms at a locus; antimicrobialcompounds include bactericides, bacteristats, fungicides, fungistats,algaecides and algistats, depending on the dose level applied, systemconditions and the level of microbial control desired. The term“microorganism” includes, for example, fungi (such as yeast and mold),bacteria and algae. The term “locus” refers to an industrial system orproduct subject to contamination by microorganisms. The followingabbreviations are used throughout the specification: ppm=parts permillion by weight (weight/weight), mL=milliliter, ATCC=American TypeCulture Collection, and MIC=minimum inhibitory concentration. Unlessotherwise specified, temperatures are in degrees centigrade (° C.), andreferences to percentages (%) are by weight. Percentages ofantimicrobial compounds in the composition of this invention are basedon the total weight of active ingredients in the composition, i.e., theantimicrobial compounds themselves, exclusive of any amounts ofsolvents, carriers, dispersants, stabilizers or other materials whichmay be present. “Salt-free” means that the composition contains zero orup to 0.5%, preferably zero or up to 0.1%, and more preferably zero orup to 0.01%, of metal salt, based on weight of the composition.

In one embodiment of the invention, the antimicrobial compositioncomprises 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one and coppertebuconazole. Preferably, a weight ratio of4,5-dichloro-2-n-octyl-4-isothiazolin-3-one to copper tebuconazole isfrom 1:400 to 1:6. Another preferred weight ratio is from 1:333 to1:6.3.

In another embodiment of the invention, the antimicrobial compositioncomprises 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one and2-methyl-4-isothiazolin-3-one. Preferably, a weight ratio of4,5-dichloro-2-n-octyl-4-isothiazolin-3-one to2-methyl-4-isothiazolin-3-one is from 1:1.4 to 1:1800. Another preferredweight ratio is from 1:1.4 to 1:1750.

In another embodiment of the invention, the antimicrobial compositioncomprises copper alkyldimethylammonium salt and copper8-hydroxyquinoline. Preferably, a weight ratio of copperalkyldimethylammonium salt to copper 8-hydroxyquinoline is from 1:0.8 to1:15. Another preferred weight ratio is from 1:1 to 1:4.

In another embodiment of the invention, the antimicrobial compositioncomprises copper alkyldimethylammonium salt and2-n-octyl-4-isothiazolin-3-one. Preferably, a weight ratio of copperalkyldimethylammonium salt to 2-n-octyl-4-isothiazolin-3-one is from1:0.02 to 1:88. Another preferred weight ratio is from 1:0.02 to 1:87.5,and another from 1:0.02 to 1:60.

In another embodiment of the invention, the antimicrobial compositioncomprises copper 8-hydroxyquinoline and 2-n-octyl-4-isothiazolin-3-one.Preferably, a weight ratio of copper 8-hydroxyquinoline to2-n-octyl-4-isothiazolin-3-one is from 1:60 to 1:0.008. Anotherpreferred weight ratio is from 1:59 to 1:0.009, and another from 1:50 to1:0.009.

In another embodiment of the invention, the antimicrobial compositioncomprises copper 8-hydroxyquinoline and3-iodo-2-propynyl-butylcarbamate. Preferably, a weight ratio of copper8-hydroxyquinoline to 3-iodo-2-propynyl-butylcarbamate is from 1:30 to1:0.2. Another preferred weight ratio is from 1:23 to 1:0.3.

In another embodiment of the invention, the antimicrobial compositioncomprises tebuconazole and a microbicide selected from the groupconsisting of 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one; copper8-hydroxyquinoline; 2-n-octyl-4-isothiazolin-3-one; and a mixture of5-chloro-2-methyl-4-isothiazolin-3-one and2-methyl-4-isothiazolin-3-one. Preferably, a weight ratio oftebuconazole to DCOIT is from 1:0.0003 to 1/0.6. Preferably, a weightratio of tebuconazole to copper 8-hydroxyquinoline is from 1/0.005 to1/1.6; another preferred weight ratio is from 1/0.006 to 1/1.58.Preferably, a weight ratio of tebuconazole to OIT is from 1/0.001 to1/0.3; another preferred weight ratio is from 1/0.002 to 1/0.24.Preferably, a weight ratio of tebuconazole to a mixture of5-chloro-2-methyl-4-isothiazolin-3-one and 2-methyl-4-isothiazolin-3-oneis from 1/0.001 to 1/0.15.

In another embodiment of the invention, the antimicrobial compositioncomprises propiconazole and a microbicide selected from the groupconsisting of 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one; copper8-hydroxyquinoline; 2-n-octyl-4-isothiazolin-3-one; a mixture of5-chloro-2-methyl-4-isothiazolin-3-one and2-methyl-4-isothiazolin-3-one; and 3-iodo-2-propynyl-butylcarbamate.Preferably, a weight ratio of propiconazole to DCOIT is from 1/0.002 to1/0.9; another preferred weight ratio is from 1/0.026 to 1/0.875.Preferably, a weight ratio of propiconazole to copper 8-hydroxyquinolineis from 1/0.02 to 1/1.5; another preferred weight ratio is from 1/0.023to 1/1.28. Preferably, a weight ratio of propiconazole to OIT is from1/0.001 to 1/0.5; another preferred weight ratio is from 1/0.0015 to1/0.48. Preferably, a weight ratio of propiconazole to a mixture of5-chloro-2-methyl-4-isothiazolin-3-one and 2-methyl-4-isothiazolin-3-oneis from 1/0.008 to 1/0.15; another preferred weight ratio is from1/0.009 to 1/0.12. Preferably, a weight ratio of propiconazole to3-iodo-2-propynyl-butylcarbamate is from 1/0.0005 to 1/0.015; anotherpreferred weight ratio is from 1/0.0007 to 1/0.011.

In another embodiment of the invention, the antimicrobial compositioncomprises DCOIT and thifluzamide. Preferably, a weight ratio of DCOIT tothifluzamide is from 1/0.1 to 1/10; another preferred weight ratio isfrom 1/0.5 to 1/2.

In another embodiment of the invention, the antimicrobial compositioncomprises copper 8-hydroxyquinoline and DCOIT. Preferably, a weightratio of copper 8-hydroxyquinoline to DCOIT is from 1/0.002 to 1/0.01;another preferred weight ratio is from 1/0.005 to 1/0.08; and another isfrom 1/0.005 to 1/0.03.

In one embodiment of the invention, those antimicrobial compositionswhich contain 2-methyl-4-isothiazolin-3-one (MI) contain relatively lowlevels of 5-chloro-2-methyl-4-isothiazolin-3-one (CMI), preferably nomore than 5%, more preferably no more than 2%, and most preferably nomore than 1.2%. Another preferred level is no more than 0.5%, andanother is no more than 0.1%. In another embodiment, CMI and MI arepresent as a mixture in a ratio from 4:1 to 1:1, preferably from 3.5:1to 2.5:1. A commercial product is available which has a CMI:MI ratio ofabout 3:1.

The antimicrobial compounds in the composition of this invention may beused “as is” or may first be formulated with a solvent or a solidcarrier. Suitable solvents include, for example, water; glycols, such asethylene glycol, propylene glycol, diethylene glycol, dipropyleneglycol, polyethylene glycol, and polypropylene glycol; glycol ethers;alcohols, such as methanol, ethanol, propanol, phenethyl alcohol andphenoxypropanol; ketones, such as acetone and methyl ethyl ketone;esters, such as ethyl acetate, butyl acetate, glycerol triacetate,TEXANOL (2,2,4-trimethyl-1,3-pentanediol, mono-isobutyrate ester;available from Eastman Co., Kingsport Tenn.), and methyl and isobutylesters of C₃-C₇ dicarboxylic acids, e.g., succinic, glutaric and adipicacids; carbonates, such as propylene carbonate and dimethyl carbonate;and mixtures thereof. It is preferred that the solvent is selected fromwater, glycols, glycol ethers, esters and mixtures thereof. Suitablesolid carriers include, for example, cyclodextrin, silicas, diatomaceousearth, waxes, cellulosic materials, alkali and alkaline earth (e.g.,sodium, magnesium, potassium) metal salts (e.g., chloride, nitrate,bromide, sulfate) and charcoal.

When an antimicrobial component is formulated in a solvent, theformulation may optionally contain surfactants. When such formulationscontain surfactants, they are generally in the form of emulsiveconcentrates, emulsions, microemulsive concentrates, or microemulsions.Emulsive concentrates form emulsions upon the addition of a sufficientamount of water. Microemulsive concentrates form microemulsions upon theaddition of a sufficient amount of water. Such emulsive andmicroemulsive concentrates are generally well known in the art. U.S.Pat. No. 5,444,078 may be consulted for further general and specificdetails on the preparation of various microemulsions and microemulsiveconcentrates.

An antimicrobial compound also can be formulated in the form of adispersion. The solvent component of the dispersion can be an organicsolvent or water, preferably water. Such dispersions can containadjuvants, for example, co-solvents, thickeners, anti-freeze agents,dispersants, fillers, pigments, surfactants, biodispersants,sulfosuccinates, terpenes, furanones, polycations, stabilizers, scaleinhibitors and anti-corrosion additives.

The antimicrobial compounds may be formulated separately or together.When both antimicrobial compounds are each first formulated with asolvent, the solvent used for the first antimicrobial compound may bethe same as or different from the solvent used to formulate the othercommercial antimicrobial compound. It is preferred that the two solventsare miscible. In the alternative, the first antimicrobial compound andthe other antimicrobial compound may be combined directly and then asolvent added to the mixture.

Those skilled in the art will recognize that the antimicrobial compoundsof the present invention may be added to a locus sequentially,simultaneously, or may be combined before being added to the locus. Itis preferred that the first antimicrobial compound and the secondantimicrobial compound be added to a locus simultaneously or combinedprior to being added to the locus. When the antimicrobial compounds arecombined prior to being added to a locus, such combination mayoptionally contain adjuvants, such as, for example, solvent, thickeners,anti-freeze agents, colorants, sequestrants (such asethylenediamine-tetraacetic acid, ethylenediaminedisuccinic acid,iminodisuccinic acid and salts thereof), dispersants, surfactants,biodispersants, sulfosuccinates, terpenes, furanones, polycations,stabilizers, scale inhibitors and anti-corrosion additives.

The antimicrobial compositions of the present invention can be used toinhibit the growth of microorganisms by introducing an antimicrobiallyeffective amount of the compositions onto, into, or at a locus subjectto microbial attack. Suitable loci include, for example: cooling towers;air washers; mineral slurries; wastewater treatment; ornamentalfountains; reverse osmosis filtration; ultrafiltration; ballast water;evaporative condensers; heat exchangers; pulp and paper processingfluids; plastics; emulsions; dispersions; paints; latices; coatings,such as varnishes; construction products, such as mastics, caulks, andsealants; construction adhesives, such as ceramic adhesives, carpetbacking adhesives, and laminating adhesives; industrial or consumeradhesives; photographic chemicals; printing fluids; household products,such as bathroom and kitchen cleaners; cosmetics; toiletries; shampoos;soaps; detergents; industrial cleaners; floor polishes; laundry rinsewater; metalworking fluids; conveyor lubricants; hydraulic fluids;leather and leather products; textiles; textile products; wood and woodproducts, such as plywood, chipboard, flakeboard, laminated beams,oriented strandboard, hardboard, and particleboard; petroleum processingfluids; fuel; oilfield fluids, such as injection water, fracture fluids,and drilling muds; agriculture adjuvant preservation; surfactantpreservation; medical devices; diagnostic reagent preservation; foodpreservation, such as plastic or paper food wrap; pools; and spas.

Preferably, the antimicrobial compositions of the present invention areused to inhibit the growth of microorganisms at a locus selected fromone or more of wood and wood products, emulsions, dispersions, paints,latices, household products, cosmetics, toiletries, shampoos, soaps,detergents, machining fluids and industrial cleaners. In particular, theantimicrobial compositions are useful in wood and wood products,emulsions, dispersions, paints and latices.

When the synergistic compositions of the present invention are used inpersonal care compositions, the formulated compositions may alsocomprise one or more ingredients selected from UV radiation-absorbingagents, surfactants, rheology modifiers or thickeners, fragrances,moisturizers, humectants, emollients, conditioning agents, emulsifiers,antistatic aids, pigments, dyes, tints, colorants, antioxidants,reducing agents and oxidizing agents.

The specific amount of the composition of this invention necessary toinhibit or control the growth of microorganisms in a locus depends uponthe particular locus to be protected. Typically, the amount of thecomposition of the present invention to control the growth ofmicroorganisms in a locus is sufficient if it provides from 0.1 to25,000 ppm active ingredient of the composition in the locus. It ispreferred that the active ingredients of the composition be present inthe locus in an amount of at least 0.5 ppm, more preferably at least 1ppm, more preferably at least 10 ppm and most preferably at least 50ppm. In one embodiment of the invention, the active ingredients arepresent in an amount of at least 500 ppm. It is preferred that theactive ingredients of the composition be present in the locus in anamount of no more than 20,000 ppm, more preferably no more than 15,000ppm, more preferably no more than 1000 ppm. In one embodiment of theinvention, the active ingredients are present in an amount of no morethan 10,000 ppm, more preferably no more than 5,000 ppm, and mostpreferably no more than 1,000 ppm.

EXAMPLES

The synergism of the combination of the present invention wasdemonstrated by testing a wide range of concentrations and ratios of thecompounds.

One measure of synergism is the industrially accepted method describedby Kull, F. C.; Eisman, P. C.; Sylwestrowicz, H. D. and Mayer, R. L., inApplied Microbiology 9:538-541 (1961), using the ratio determined by theformula:C _(a) /C _(A) +C _(b) /C _(B)=Synergy Index (“SI”)wherein:

-   -   C_(A)=concentration of compound A (first component) in ppm,        acting alone, which produced an end point (MIC of Compound A).    -   C_(a)=concentration of compound A in ppm, in the mixture, which        produced an end point.    -   C_(B)=concentration of compound B (second component) in ppm,        acting alone, which produced an end point (MIC of Compound B).    -   C_(b)=concentration of compound B in ppm, in the mixture, which        produced an end point.

When the sum of C_(a)/C_(A) and C_(b)/C_(B) is greater than one,antagonism is indicated. When the sum is equal to one, additivity isindicated, and when less than one, synergism is demonstrated. The lowerthe SI, the greater the synergy shown by that particular mixture. Theminimum inhibitory concentration (MIC) of an antimicrobial compound isthe lowest concentration tested under a specific set of conditions thatprevents the growth of added microorganisms.

Synergy tests were conducted using standard microtiter plate assays withmedia designed for optimal growth of the test microorganism. Minimalsalt medium supplemented with 0.2% glucose and 0.1% yeast extract (M9GYmedium) was used for bacteria testing; Potato Dextrose Broth (PDBmedium) was used for yeast and mold testing. In this method, a widerange of combinations of microbicides was tested by conducting highresolution MIC assays in the presence of various concentrations ofbiocides. High resolution MICs were determined by adding varying amountsof microbicide to one column of a microtitre plate and doing subsequentten-fold dilutions using an automated liquid handling system to obtain aseries of end points ranging of active ingredient. The synergy of thecombinations of the present invention was determined against twobacteria, Pseudomonas aeruginosa (Ps. aeruginosa—ATCC #9027) andStaphylococcus aureus (S. aureus—ATCC #6538), a yeast, Candida albicans(C. albicans—ATCC #10231), and a mold, Aspergillus niger (A. niger—ATCC16404). The bacteria were used at a concentration of about 1-6×10⁶bacteria per mL and the yeast and mold at 1-5×10⁵ fungi per mL. Thesemicroorganisms are representative of natural contaminants in manyconsumer and industrial applications. The plates were visually evaluatedfor microbial growth (turbidity) to determine the MIC after variousincubation times at 25° C. (yeast and mold) or 30° C. (bacteria).

The test results for demonstration of synergy of the microbicidecombinations of the present invention are shown below in the Tables.Each table shows the specific combinations of Component (a) and thesecond component (b); results against the microorganisms tested withincubation times; the end-point activity in ppm measured by the MIC forComponent (a) (C_(a)), for the second component alone (C_(b)), for themixture (C_(a)) and for second component in the mixture (C_(b)); thecalculated SI value; and the range of synergistic ratios for eachcombination tested (first component/second component or a+b).

An application test was performed to evaluate synergy ofDCOIT/thifluzamide alone and in combination against Gloeophyllum trabeum(G. trabeum—ATCC #11593) and Trametes vesicolor (T. vesicolor—ATCC#4262). A paper disc was dipped in the treatment solution, air dried andplaced on Malt agar plate streaked with the test organisms. The surfaceof the disc was also swabbed with the test organisms. The agar plateswere incubated at 25° C. for 4 weeks. Fungal growth was then observedvisually.

The following Tables summarize data for combinations of biocides againstfungi and bacteria, along with their synergy index (SI) and the weightratios of biocides. All amounts of biocides are reported as ppm ofactive ingredient.

Ca = Component A (DCOIT) Cb = Component B (MI) Ratio = Ca/Cb TestOrganisms Contact Time Ca Cb S.I. Ca/Cb Ps. Aeruginosa 24 hour 3.2 — — —ATCC #9027 — 20 — — 0.7 15 0.97  1/21.5 48 hour 5.3 — — — — 20 — — 3.9 50.99 1/1.3  2.6 10 0.99 1/3.8  1.8 10 0.84 1/5.6  1.2 15 0.98  1/12.51.8 15 1.09 1/8.3  3.2 10 1.1 1/3.1  S. aureus 24 hour 0.1 — — — ATCC#6538 — 30 — — 0.04 20 1.07 0 48 hour 0.4 — — — — 40 — — 0.1 25 0.881/250 0.04 30 0.85 1/750 0.06 30 0.9 1/500 0.1 30 1 1/300 A. niger 3days 1 — — — ATCC #16404 — 450 — — 0.55 200 0.99 2/727 0.44 250 1 1/5680.26 300 0.93  1/1153 0.33 300 1 1/909 0.26 350 1.04  1/1346 7 days 1 —— — — 450 — — 0.3 300 0.97  1/1000

Ca = Component A (ACQ-C)¹ Cb = Component B (copper 8-hydroxyquinoline)Ratio = Ca/Cb Test Organisms Contact Time Ca Cb S.I. Ca/Cb S. aureus 48hour 2 — — — ATCC #6538 — 3 — — 0.53 1 0.6  1/2  0.65 1 0.66 1/1.5 0.881 0.77 1/1.4 1.1 1 0.88 1/0.9 0.53 2 0.93 1/4  0.65 2 0.99 1/3  0.88 21.11 1/2.3 A. niger 3 days 32 — — — ATCC #16404 — 7 — — 6.6 5 0.92 1/0.87 days 32 — — — — 8 — — 6.6 6 0.96 1/0.9 C. albicans 24 hour 4.6 — — —ATCC #10231 — 15  — — 2.1 5 0.79 1/2.4 3 5 0.99 1/1.7 0.8 10  0.84 1/12.5 1.4 10  0.97 1/7.1 48 hour 6.1 — — — — 20  — — 2.1 5 0.59 1/2.43 5 0.74 1/1.7 4.6 5 1   1/1.1 1.4 15  0.98  1/10.7 ¹“ACQ-C” is aformulation of copper oxide monoethanolamine complex with alkylbenzyldimethylammonium chloride, wherein the alkyl group is a mixture ofC₈-C₁₈ alkyls, with the majority being C₁₂ and C₁₄, and the weight ratioof copper oxide to alkyl benzyldimethylammonium chloride is from 62:38to 71:29.

Ca = Component A (copper 8-hydroxyquinoline) Cb = Component B (OIT)Ratio = Ca/Cb Test Organisms Contact Time Ca Cb S.I. Ca/Cb Ps.Aeruginosa 48 hour 7 — — — ATCC #9027 — 415 — — 3 180 0.86 1/60  3 2551.04 1/85  S. aureus 24 hour 3 — — — ATCC #6538 — 63 — — 1 36 0.9  1/36 2 13.2 0.88 1/6.6  2 24 1.05 1/12  48 hour 4 — — — — 78 — — 1 51 0.9 1/51  1 63 1.06 1/63  2 36 0.96 1/18  3 13.2 0.92 1/4.4  C. albicans 24hour 15  — — — ATCC #10231 — 0.6 — — 5 0.33 0.88 1/0.06 10  0.09 0.821/0.01 10  0.13 0.88 1/0.01 10  0.16 0.93 1/0.02 10  0.2 1   1/0.02 48hour 15  — — — — 0.9 — — 10  0.2 0.89 1/0.02 10  0.26 0.96 1/0.03 5 0.61   1/0.02

Ca = Component A (ACQ-C) Cb = Component B (OIT) Ratio = Ca/Cb TestOrganisms Contact Time Ca Cb S.I. Ca/Cb Ps. Aeruginosa 24 hour 20 — — —ATCC #9027 — 390 — — 5 315 1.06 1/63  15 129 1.06 1/8.6  48 hour 20 — —— — 525 — — 10 255 0.99 1/25.5 15 180 1.09 1/12  S. aureus 24 hour 1 — —— ATCC #6538 — 63 — — 0.4 24 0.78 1/60  0.6 24 0.98 1/40  0.4 36 0.971/90  0.6 10.5 0.77 1/17.5 0.8 10.5 0.97 1/13.1 48 hour 2 — — — — 78 — —0.8 51 1.05 1/63.8 C. albicans 24 hour 8 — — — ATCC #10231 — 0.6 — — 20.3 0.75 1/0.15 4 0.3 1   1/0.08 48 hour 8 — — — — 0.9 — — 2 0.6 0.921/0.3  A. niger 3 days 30 — — — ATCC #16404 — 3.3 — — 5 1 0.47 1/0.2  51.5 0.62 1/0.3  5 2.1 0.8  1/0.4  5 2.6 0.95 1/0.5  10 0.33 0.43 1/0.0310 0.44 0.47 1/0.04 10 0.55 0.5  1/0.06 10 1 0.64 1/0.1  20 0.33 0.77 1/0.017 7 days 30 — — — — 3.3 — — 10 1 0.64 1/0.1  10 1.5 0.79 1/0.1510 2.1 0.97 1/0.21 20 1 0.97 1/0.05

Ca = Component A (copper 8-hydroxyquinoline) Cb = Component B (IPBC)Ratio = Ca/Cb Test Organisms Contact Time Ca Cb S.I. Ca/Cb Ps.Aeruginosa 24 hour 7 — — — ATCC #9027 — 263 — — 2 195 1.03  1/97.5 3 1581.03  1/52.7 4 60 0.8  1/15  4 90 0.91  1/22.5 5 60 0.94 1/12  48 hour 7— — — — 263 — — 3 128 0.92  1/42.7 3 158 1.03  1/52.7 4 128 1.06 1/32 S. aureus 24 hour 3 — — — ATCC #6538 — 34 — — 1 8.8 0.59 1/8.8 1 16 0.8 1/16  2 24 1.04 1/24  2 8.8 0.93 1/4.4 2 4.2 0.79 1/2.1 2 5.2 0.82 1/2.62 7 0.87 1/3.5 2 8.8 0.93 1/4.4 48 hour 3 — — — — 42 — — 1 8.8 0.541/8.8 1 16 0.71 1/16  1 24 0.9  1/24  2 8.8 0.88 1/4.4 2 5 0.77 1/2.5 216 1.05 1/8  2 5.2 0.79 1/2.6 2 7 0.83 1/3.5 2 5.2 0.79 1/2.6 2 8.8 0.881/4.4 C. albicans 24 hour 15  — — — ATCC #10231 — 4.2 — — 5 1.6 0.71 1/0.32 5 2.4 0.9   1/0.48 10  1.6 1.05 1/1.6 48 hour 15  — — — — 4.2 —— 5 2.4 0.9   1/0.48

Ca = Component A (DCOIT) Cb = Component B (Cu-tebuconazole complex)Ratio = Ca/Cb Test Organisms Contact Time Ca Cb S.I. Ca/Cb Ps.Aeruginosa 24 hour 3.2 — — — ATCC #9027 — 150 — — 1.8 25 0.73 1/13.90.32 100 0.77 1/313  0.39 100 0.79 1/256  0.66 100 0.87 1/152  1.2 1001.04 1/83  48 hour 5.3 — — — — 200 — — 1.8 25 0.46 1/13.9 3.2 25 0.731/7.8  3.9 25 0.86 1/6.4  1.8 50 0.59 1/27.8 1.8 100 0.84 1/55.6 1.8 1501.09 1/83.3 0.39 100 0.57  1/256.4 0.66 100 0.62  1/151.5 1.2 100 0.731/83.3 1.8 100 0.84 1/55.6 0.53 150 0.85 1/283  1.2 100 0.73 1/83.3 1.8100 0.84 1/55.6 S. aureus 24 hour 0.1 — — — — 40 — — 0.02 35 0.79 1/1750 A. niger 3 days 1.5 — — — ATCC #16404 — 80 — — 0.44 40 0.791/90.9 0.55 40 0.87 1/72.7 0.44 50 0.92  1/113.6 0.4 60 1.04 1/150  0.3360 0.97  1/181.8 7 days 2.1 — — — — 80 — — 0.55 40 0.76 1/72.7 1 40 0.981/40  0.55 50 0.89 1/90.9 0.55 60 1.01 1/109  0.5 50 0.88 1/100 

Ca = Component A (copper 8-hydroxyquinoline) Cb = Component B(Cu-tebuconazole complex) Ratio = Ca/Cb Test Organisms Contact Time CaCb S.I. Ca/Cb Ps. aureginosa 24 hour 7 — — — ATCC #9027 — 195  — — 4 600.88 1/15 5 60 1.02 1/12 S. aureus 24 hour 4 — — — ATCC #6538 — 44 — — 221 0.98  1/10.5 48 hour 4 — — — — 44 — — 1 26 0.84 1/26 1 33 1   1/33 226 1.09 1/13

Ca = Component A (copper 8-hydroxyquinoline) Cb = Component B (DCOIT)Ratio = Ca/Cb Test Organisms Contact Time Ca Cb S.I. Ca/Cb Ps.aureginosa 24 hour 7 — — — ATCC #9027 — 3.2 — — 3 1.8 1 1/0.6  48 hour 7— — — — 5.3 — — 2 3.9 1.02 1/2    S. aureus 24 hour 3 — — — ATCC #6538 —0.1 — — 2  0.01 0.8 1/0.005 1  0.03 0.6 1/0.03  2  0.03 1 1/0.015

Ca = Component A (tebuconazole) Cb = Component B (copper8-hydroxyquinoline) Ratio = Ca/Cb Test Organisms Contact Time Ca Cb S.I.Ca/Cb Ps. Aeruginosa 24 hour 900 — — — ATCC #9027 — 7 — — 200 2 1.061/0.01  S. aureus 24 hour 50 — — — — 3.3 — — 40 0.3 0.89 1/0.008 30 0.40.72 1/0.01  20 0.4 0.52 1/0.02  50 0.3 1.09 1/0.06  40 0.4 0.92 1/0.01 48 hour 50 — — — — 4.4 — — 40 0.6 0.94 1/0.015 30 1 0.83 1/0.033 20 10.63 1/0.05  40 1 1.03 1/0.025 C. albicans 24 hour 60 — — — ATCC #10231— 15.8 — — 50 0.3 0.85 1/0.006 50 0.6 0.87 1/0.012 50 1.3 0.92 1/0.02650 1.6 0.93 1/0.032 50 2 0.96 1/0.04  50 2.6 1 1/0.052 50 3.3 1.041/0.066 40 0.3 0.69 1/0.008 40 0.6 0.7 1/0.015 40 0.9 0.72 1/0.023 401.3 0.75 1/0.033 40 1.6 0.77 1/0.04  40 2 0.79 1/0.05  40 2.6 0.831/0.065 40 3.3 0.88 1/0.083 40 6 1.05 1/0.15  30 0.6 0.54 1/0.02  30 0.90.56 1/0.03  30 1.3 0.58 1/0.043 30 1.6 0.6 1/0.053 30 2 0.63 1/0.067 302.6 0.66 1/0.087 30 3.3 0.71 1/0.11  30 6 0.88 1/0.2  30 9 1.07 1/0.3 20 1.3 0.42 1/0.065 20 1.6 0.43 1/0.08  20 2 0.46 1/0.1  20 2.6 0.51/0.13  20 3.3 0.54 1/0.165 20 6 0.71 1/0.3  20 9 0.9 1/0.45  10 3.30.38 1/0.33  10 6 0.54 1/0.6  10 9 0.74 1/0.9  10 12.8 0.98 1/1.28  48hour 60 — — — — 19.5 — — 50 0.6 0.86 1/0.012 50 0.9 0.88 1/0.018 50 1.30.9 1/0.026 50 1.6 0.92 1/0.032 50 2 0.94 1/0.04  50 2.6 0.97 1/0.052 503.3 1 1/0.066 40 0.6 0.7 1/0.015 40 0.9 0.71 1/0.023 40 1.3 0.73 1/0.03340 1.6 0.75 1/0.04  40 2 0.77 1/0.05  40 2.6 0.8 1/0.065 40 3.3 0.841/0.083 40 6 0.97 1/0.15  30 2 0.6 1/0.067 30 2.6 0.63 1/0.087 30 3.30.67 1/0.11  30 6 0.81 1/0.2  30 9 0.96 1/0.3  20 3.3 0.5 1/0.165 20 60.64 1/0.3  20 9 0.79 1/0.45  20 12.8 0.99 1/0.64  10 6 0.47 1/0.6  10 90.63 1/0.9  10 12.8 0.82 1/1.28  10 15.8 0.98 1/1.58  A. niger 3 days 8— — — ATCC #16404 — 6 — — 7 0.36 0.94 1/0.05  7 0.51 0.96 1/0.07  7 0.630.98 1/0.09  7 0.78 1.01 1/0.11  6 0.36 0.81 1/0.06  6 0.51 0.84 1/0.0856 0.63 0.86 1/0.105 6 0.78 0.88 1/0.13  6 1.05 0.93 1/0.175 6 1.32 0.971/0.22  6 2 1.08 1/0.33  5 0.78 0.76 1/0.156 5 1.05 0.8 1/0.21  5 1.320.85 1/0.264 5 2 0.96 1/0.4  4 0.78 0.63 1/0.195 4 1.05 0.68 1/0.263 41.32 0.72 1/0.33  4 2 0.83 1/0.5  3 2 0.71 1/0.67  3 4 1.04 1/1.33  2 20.58 1/1    2 4 0.92 1/2    7 days 8 — — — — 6 — — 7 0.36 0.94 1/0.051 70.51 0.96 1/0.073 7 0.63 0.98 1/0.09  7 0.78 1.01 1/0.11  6 0.36 0.811/0.06  6 0.51 0.84 1/0.085 6 0.63 0.86 1/0.105 6 0.78 0.88 1/0.13  61.05 0.93 1/0.175 6 1.32 0.97 1/0.22  5 0.78 0.755 1/0.156 5 1.05 0.81/0.21  5 1.32 0.845 1/0.264 5 2 0.96 1/0.4  4 0.78 0.63 1/0.195 4 1.050.68 1/0.263 4 1.32 0.72 1/0.33  4 2 0.83 1/0.5  3 2 0.71 1/0.67  3 41.04 1/1.33  2 4 0.92 1/2   

TABLE 10 Ca = Component A (tebuconazole) Cb = Component B (DCOIT) Ratio= Ca/Cb Test Organisms Contact Time Ca Cb S.I. Ca/Cb Ps. Aeruginosa 48hour 900 — — — ATCC #9027 — 3.9 — — 50 2.6 0.72 1/0.052 100 2.6 0.781/0.026 200 2.6 0.89 1/0.013 300 1.8 0.79 1/0.006 400 1.8 0.91 1/0.005500 1.8 1.02 1/0.004 S. aureus 24 hour 50 — — — — 0.2 — — 40 0.01 0.85 1/0.0003 30 0.02 0.7  1/0.0007 40 0.02 0.9  1/0.0005 40 0.03 0.95 1/0.0008 40 0.04 1 1/0.001 48 hour 50 — — — — 0.3 — — 40 0.04 0.931/0.001 30 0.1 0.93 1/0.003 A. niger 3 days 8 — — — ATCC #16404 — 1.8 —— 6 0.32 0.93 1/0.053 6 0.39 0.97 1/0.065 5 0.32 0.8 1/0.064 5 0.39 0.841/0.078 5 0.53 0.92 1/0.106 5 0.66 0.99 1/0.132 4 0.32 0.68 1/0.08  40.39 0.72 1/0.098 4 0.53 0.79 1/0.133 4 0.66 0.87 1/0.165 3 0.39 0.591/0.13  3 0.53 0.67 1/0.177 3 0.66 0.74 1/0.22  3 1.2 1.04 1/0.4  2 1.20.92 1/0.6  7 days 8 — — — — 3.2 — — 7 0.32 0.98 1/0.046 6 0.39 0.871/0.065 6 0.53 0.92 1/0.088 6 0.66 0.96 1/0.11  5 0.53 0.79 1/0.106 50.39 0.75 1/0.078 5 0.53 0.79 1/0.106 5 0.66 0.83 1/0.132 4 0.53 0.671/0.133 4 0.66 0.71 1/0.165 4 1.2 0.88 1/0.3 

Ca = Component A (tebuconazole) Cb = Component B (OIT) Ratio = Ca/CbTest Organisms Contact Time Ca Cb S.I. Ca/Cb Ps. Aeruginosa 24 hour 900— — — ATCC #9027 — 390 — — 800 66 1.06 1/0.083 700 120 1.09 1/0.17  600120 0.97 1/0.2  500 120 0.86 1/0.24  48 hour 900 — — — — 390 — — 500 1801.02 1/0.36  S. aureus 24 hour 50 — — — — 63 — — 10 51 1.01 1/5.1  C.albicans 24 hour 50 — — — ATCC #10231 — 0.9 — — 40 0.02 0.82 1/0.005 400.026 0.83  1/0.0007 40 0.033 0.84  1/0.0008 40 0.06 0.87 1/0.015 400.09 0.90  1/0.0023 40 0.13 0.94  1/0.0033 40 0.16 0.98 1/0.004 30 0.060.67 1/0.002 30 0.09 0.70 1/0.003 30 0.13 0.74 1/0.004 30 0.16 0.781/0.005 30 0.2 0.82  1/0.0067 30 0.26 0.89  1/0.0087 30 0.33 0.971/0.011 20 0.33 0.77  1/0.0165

Ca = Component A (tebuconazole) Cb = Component B (CMIT/MIT) Ratio =Ca/Cb Test Organisms Contact Time Ca Cb S.I. Ca/Cb S. aureus 24 hour 50— — — — 1 — — 40 0.04 0.84 1/0.001 30 0.06 0.66 1/0.002 20 0.1 0.5 1/0.005 10 0.27 0.47 1/0.027 10 0.33 0.53 1/0.033 10 0.44 0.64 1/0.04410 0.55 0.75 1/0.055 20 0.15 0.55 1/0.008 20 0.21 0.61 1/0.011 20 0.260.66 1/0.013 20 0.32 0.72 1/0.016 20 0.44 0.84 1/0.022 20 0.55 0.951/0.028 20 0.21 0.61 1/0.011 30 0.1 0.7  1/0.003 30 0.15 0.75 1/0.005 300.21 0.81 1/0.007 30 0.26 0.86 1/0.008 30 0.32 0.92 1/0.011 30 0.44 1.041/0.015 40 0.06 0.86 1/0.002 40 0.1 0.9  1/0.003 40 0.15 0.95 1/0.004 400.21 1.01 1/0.005 40 0.26 1.06 1/0.007 48 hour 50 — — — — 3 — — 40 0.10.83 1/0.003 40 0.15 0.85 1/0.004 40 0.21 0.87 1/0.005 40 0.26 0.891/0.007 40 0.33 0.91 1/0.008 40 0.55 0.98 1/0.014 30 0.33 0.71 1/0.01130 0.55 0.78 1/0.018 30 1 0.93 1/0.033 20 1 0.73 1/0.05  20 2 1.071/0.1  C. albicans 24 hour 50 — — — ATCC #10231 — 2.1 — — 40 0.1 0.85 1/0.0025 40 0.15 0.87  1/0.0038 40 0.21 0.90  1/0.0053 40 0.26 0.92 1/0.0065 40 0.33 0.96  1/0.0083 30 0.15 0.67 1/0.005 30 0.21 0.701/0.007 30 0.26 0.72  1/0.0087 30 0.33 0.76 1/0.011 30 0.44 0.81 1/0.01530 0.55 0.86 1/0.018 20 0.55 0.66 1/0.028 20 1 0.88 1/0.05  10 1.5 0.911/0.15  48 hour 50 — — — — 2.6 — — 30 0.55 0.81 1/0.018 30 1 0.981/0.033 20 1.5 0.98 1/0.075

Ca = Component A (propiconazole) Cb = Component B (copper8-hydroxyquinoline) Ratio = Ca/Cb Test Organisms Contact Time Ca Cb S.I.Ca/Cb S. aureus 24 hour 100  — — — — 3.3 — — 90 0.6 1.08 1/0.007 70 11   1/0.014 60 1.5 1.05 1/0.025 50 1.5 0.95 1/0.03  40 2.1 1.04 1/0.05348 hour 100  — — — — 3.3 — — 90 0.6 1.08 1/0.007 C. albicans 24 hour 50— — — ATCC #10231 — 19.5 — — 40 0.9 0.85 1/0.023 40 1.3 0.87 1/0.033 401.6 0.88 1/0.04  40 2 0.90 1/0.05  40 2.6 0.93 1/0.065 40 3.3 0.971/0.083 30 2.6 0.73 1/0.087 30 3.3 0.77 1/0.11  30 6 0.91 1/0.2  20 90.86 1/0.45  20 12.8 1.06 1/0.64  10 9 0.66 1/0.9  10 12.8 0.86 1/1.28 48 hour 50 — — — — 19.5 — — 40 1.3 0.87 1/0.033 40 1.6 0.88 1/0.04  40 20.90 1/0.05  40 2.6 0.93 1/0.065 40 3.3 0.97 1/0.083 30 2.6 0.73 1/0.08730 3.3 0.77 1/0.11  30 6 0.91 1/0.2  A. niger 3 days 20 — — — ATCC#16404 — 6 — — 15 1.3 0.97 1/0.087 10 2 0.83 1/0.2  7 days 25 — — — — 6— — 15 2 0.93 1/0.93 

Ca = Component A (propiconazole) Cb = Component B (DCOIT) Ratio = Ca/CbTest Organisms Contact Time Ca Cb S.I. Ca/Cb S. aureus 24 hour 100  — —— — 0.2 — — 90 0.2 1   1/0.002 90  0.03 1.05 1/0.003 A. niger 3 days 20— — — ATCC #16404 — 2.6 — — 15  0.39 0.90 1/0.026 15  0.53 0.95 1/0.03510  0.66 0.75 1/0.066 10 1.2 0.96 1/0.12   5 1.8 0.94 1/0.36  7 days 20— — — — 3.2 — — 10 1.2 0.88 1/0.875

Ca = Component A (propiconazole) Cb = Component B (OIT) Ratio = Ca/CbTest Organisms Contact Time Ca Cb S.I. Ca/Cb Ps. Aeruginosa 24 hour 800 — — — ATCC #9027 — 390 — — 500  180 1.09 1/0.36 48 hour 800  — — — — 525— — 600  180 1.09 1/0.3  S. aureus 24 hour 100  — — — — 63 — — 90 0.40.91  1/0.004 80 0.6 0.81  1/0.008 70 2.4 0.74  1/0.034 60 2.4 0.641/0.04 50 13 0.71 1/0.26 50 24 0.88 1/0.48 50 36 1.07 1/0.72 60 24 0.981/0.4  70 10.5 0.87 1/0.25 70 13.2 0.91 1/0.19 70 24 1.08 1/0.34 80 13.21.01  1/0.167 90 10.5 1.07 1/0.12 48 hour 100  — — — — 78 — — 90 0.80.91  1/0.009 80 1.1 0.81  1/0.014 70 6.3 0.78 1/0.09 60 7.8 0.7  1/0.1350 13 0.67 1/0.26 40 51 1.05 1/1.28 50 36 0.96 1/0.72 60 24 0.91 1/0.4 60 36 1.06 1/0.6  70 24 1.01 1/0.34 80 13 0.97 1/0.16 90 13 1.07 1/0.1490 10.5 1.03 1/0.12 C. albicans 24 hour 50 — — — ATCC #10231 — 1.3 — —40 0.06 0.85  1/0.0015 30 0.06 0.65  1/0.002 20 0.33 0.65  1/0.0165 100.6 0.66 1/0.06 40 0.09 0.87  1/0.0023 40 0.13 0.90  1/0.0033 40 0.160.92  1/0.004 40 0.2 0.95  1/0.005 30 0.09 0.67  1/0.003 30 0.13 0.70 1/0.004 30 0.16 0.72  1/0.005 30 0.2 0.75  1/0.007 30 0.26 0.80 1/0.009 30 0.33 0.85  1/0.011 20 0.6 0.86 1/0.03 10 0.9 0.89 1/0.09 48hour 50 — — — — 1.3 — — 40 0.09 0.87  1/0.0023 20 0.6 0.86 1/0.03 400.13 0.90  1/0.003 40 0.16 0.92  1/0.004 40 0.2 0.95  1/0.005

Ca = Component A (propiconazole) Cb = Component B (CMIT/MIT) Ratio =Ca/Cb Test Organisms Contact Time Ca Cb S.I. Ca/Cb S. aureus 24 hour100  — — — — 1 — — 60 0.44 1.04 1/0.007 50 0.44 0.94 1/0.009 40 0.440.84 1/0.011 40 0.55 0.95 1/0.014 50 0.55 1.05 1/0.011 C. albicans 24hour 50 — — — ATCC #10231 — 2.6 — — 40 0.44 0.97 1/0.011 30 1 0.981/0.033 20 1.5 0.98 1/0.075 A. niger 3 days 20 — — — ATCC #16404 — 2.6 —— 15 0.4 0.90 1/0.027 10 1.2 0.96 1/0.12 

Ca = Component A (propiconazole) Cb = Component B (IPBC) Ratio = Ca/CbTest Organisms Contact Time Ca Cb S.I. Ca/Cb A. niger 3 days 20 — — —ATCC #16404 — 0.4  — — 15 0.01 0.78 1/0.0007 15 0.02 0.80 1/0.0013 150.03 0.83 1/0.002  15 0.04 0.85 1/0.0027 15 0.05 0.88 1/0.0033 15 0.070.93 1/0.0047 15 0.09 0.98 1/0.006  10 0.11 0.78 1/0.011 

Ca = Component A (DCOIT) Cb = Component B (thifluzamide) Ratio = Ca/CbTest Organisms Contact Time Ca Cb S.I. Ca/Cb G. trabeum 4 weeks 320 — —— ATCC #11539 — >960 — —  80 80 <0.33 1/1 T. vesicolor 4 weeks 320 — — —ATCC #42462 — 320 — —  80 80 0.5 1/1

1. A synergistic antimicrobial composition comprising: (a) a copperalkylbenzyldimethylammonium salt; and (b)2-n-octyl-4-isothiazolin-3-one.
 2. The composition of claim 1 wherein aweight ratio of copper alkylbenzyldimethylammonium salt to2-n-octyl-4-isothiazolin-3-one is from 1:0.02 to 1:60.